The general principle of solar thermal technology is based on the concept of the concentration of solar radiation to heat a heat-transfer fluid and generate electricity. Solar energy collection and its concentration is one of the greatest challenges in the development of solar thermal power plants. There are mainly two types of solar concentrators: linear concentrators and point concentrators.
Within point concentrators parabolic disc and tower central concentrators can be distinguished. Within linear technology, the Parabolic Cylinder Concentrator (PCC) is the more mature concentration system and now the new Fresnel-type Linear Concentrators (FLC) are starting to emerge.
In the case of the Fresnel technology plants, these are composed of a primary and a secondary system. The primary system consists of a series of parallel rows of flat or slightly curved reflecting mirrors, with mobile structures that are responsible for emitting and guiding solar radiation to the secondary system.
The mirrors of the Fresnel primary field should refocus the light in the secondary. To optimize solar concentration and that the rays enter into the secondary reconcentrator it is necessary to curve the mirrors.
In the case of the tower plants, the mirrors or heliostats reflect all the solar radiation on a point or focus located at the top of a tower, which is why these mirrors are also curved, with the purpose of concentrating all the solar radiation on said focus.
This type of facilities should be very cheap in order to be competitive. Therefore, buying flat primary mirrors and then mechanically curving them before mounting the rows of the primary is cheaper that buying the directly curved mirrors.
In general, the known state of the art works the idea of creating a mold for each desired curvature, with the increase of costs and the lack of precision that this entails, because it is so expensive to create a mold for each curvature required in the field that the aim is to homogenize the manufacture, at the expense of losing quality and efficiency in the system.
Therefore, the solution proposed by the invention passes by having a single mirror curving bench which allows curving the mirrors with any desired curvature, without having to make a mold for each development.
The filed invention enables carrying out this task.